Posted: 10/10/2015 at 09:29
Thanks for the comments folks.
Tom as others have suggested you have a lot of pace already so you could be in for a top debut.
And re the P&D schedule it has plenty of long and medium long runs (and they're not easy because of the pace). The schedule is brilliant for getting you in optimum marathon shape. I followed the up to 85mpw one to the letter and it got me a sub 2:30. And yes it has a few runs over 20. Nothing excessive but for a first one as TR aludes to its all about reaching the startling fit and uninsured. P&D is such a well balanced plan and I couldn't recommend it highly enough for someone likeyourself who clearly has some running talent and is tackling their first marathon.
Maybe after you've done a couple then start thinking about what bits really work for you and whether full/over distance are necessary. I get a lot of comfort out of doing a couple over/full distance but I have done 16 of them now so know what works best for me and importantly what I can get away with!